Block #149,832

TWNLength 9★☆☆☆☆

Bi-Twin Chain · Discovered 9/4/2013, 3:01:18 PM · Difficulty 9.8580 · 6,653,501 confirmations

TWN
Bi-Twin Chain

Interleaved pairs of primes that differ by 2, forming twin prime pairs at each level.

Block Header
Block Hash
9a6246e18c75952a28deac1bfe77c5d1db75f7b5b11b7e2bed313906d4b23089

Height

#149,832

Difficulty

9.857984

Transactions

3

Size

1.05 KB

Version

2

Bits

09dba4df

Nonce

117,919

Timestamp

9/4/2013, 3:01:18 PM

Confirmations

6,653,501

Merkle Root

5e9d2e65bfa1072599796a825ca147c4f4677fa05eef45ae7dbf14365d366196
Transactions (3)
Prime Chain Origin

This is the prime chain origin stored in the block header. It is a composite number (not prime itself) — it equals the first prime in the chain multiplied by a primorial. The origin anchors the entire chain to this specific block.

2.822 × 10⁹³(94-digit number)
28226328600502329736…00865526297070687879
Discovered Prime Numbers
Lower: 2^k × origin − 1 | Upper: 2^k × origin + 1

These are the actual prime numbers discovered by this block, computed using the verified Primecoin formula. Each number has been independently confirmed to pass the Fermat primality test. Use the FactorDB links to verify any number independently.

Level 0 — Twin Prime Pair (origin ± 1)
origin − 1
2.822 × 10⁹³(94-digit number)
28226328600502329736…00865526297070687879
Verify on FactorDB ↗Wolfram Alpha ↗
origin + 1
2.822 × 10⁹³(94-digit number)
28226328600502329736…00865526297070687881
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: origin + 1 − origin − 1 = 2 (twin primes ✓)
Level 1 — Twin Prime Pair (2^1 × origin ± 1)
2^1 × origin − 1
5.645 × 10⁹³(94-digit number)
56452657201004659473…01731052594141375759
Verify on FactorDB ↗Wolfram Alpha ↗
2^1 × origin + 1
5.645 × 10⁹³(94-digit number)
56452657201004659473…01731052594141375761
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^1 × origin + 1 − 2^1 × origin − 1 = 2 (twin primes ✓)
Level 2 — Twin Prime Pair (2^2 × origin ± 1)
2^2 × origin − 1
1.129 × 10⁹⁴(95-digit number)
11290531440200931894…03462105188282751519
Verify on FactorDB ↗Wolfram Alpha ↗
2^2 × origin + 1
1.129 × 10⁹⁴(95-digit number)
11290531440200931894…03462105188282751521
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^2 × origin + 1 − 2^2 × origin − 1 = 2 (twin primes ✓)
Level 3 — Twin Prime Pair (2^3 × origin ± 1)
2^3 × origin − 1
2.258 × 10⁹⁴(95-digit number)
22581062880401863789…06924210376565503039
Verify on FactorDB ↗Wolfram Alpha ↗
2^3 × origin + 1
2.258 × 10⁹⁴(95-digit number)
22581062880401863789…06924210376565503041
Verify on FactorDB ↗Wolfram Alpha ↗
Difference: 2^3 × origin + 1 − 2^3 × origin − 1 = 2 (twin primes ✓)
Level 4 — Twin Prime Pair (2^4 × origin ± 1)
2^4 × origin − 1
4.516 × 10⁹⁴(95-digit number)
45162125760803727578…13848420753131006079
Verify on FactorDB ↗Wolfram Alpha ↗

What this block proved

The miner who found this block proved the existence of 9 consecutive prime numbers forming a Bi-Twin Chain. The prime chain origin — the large number shown above — anchors the chain and is divisible by a primorial (the product of small primes), cryptographically tying these prime numbers to this specific block.

★☆☆☆☆
Rarity
CommonChain length 9

Found in most blocks. The baseline for Primecoin's proof-of-work.

How Primecoin's Proof-of-Work Constructs These Primes

Primecoin stores a value called the prime chain origin in each block. The miner found a large integer such that when divided by a primorial (the product of small primes: 2 × 3 × 5 × 7 × …), the result is the first prime in the chain. The origin is deliberately divisible by this primorial — that divisibility is part of the proof.

Prime Chain Origin = First Prime × Primorial (2·3·5·7·11·…)
Source: Primecoin prime.cpp — CheckPrimeProofOfWork()

This is why the origin has many small prime factors — those factors are the primorial divisor. The chain then extends from the first prime using the TWN formula:

TWN: twin pairs (p, p+2) where p = origin/primorial − 1 and p+2 = origin/primorial + 1
Circulating Supply:57,670,696 XPM·at block #6,803,332 · updates every 60s
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